The Contractor will examine the additive and potentially synergistic activities of two potential adjuvants as a combined adjuvant: low molecular weight hyaluronan (Haf) and the A1 subunit of the Escherichia coli heat-labile enterotoxin (LTA). The adjuvants will be examined in the context of protection against Bordetella pertussis, the causative agent of pertussis (whooping cough).